Regarding APC kiosks, what happens when one member of the family is entering the US with an ESTA form and the other one with a B1/B2 Visa? Can they use the APC kiosk together? At certain moment, the system asks whether you are travelling under visa waiver program or B1/B2 visa or if you are a US or Canadian passport holder or if you have a green card. In my case, I will select “travelling with ESTA” but I’m afraid that when choosing “yes” to the question “are you travelling with other member of your family?” the system will only require to repeat passport scanning and fingerprints for the second person and will not ask the form of entry which is different from mine. Hope the question is clear.
Ask the person at the kiosks. Clearly state that you're both traveling together under different visas and ask what you should do.
Make this clear the CBP officer also. The officer will likely want to know why a B1/B2 visa holder are traveling together and will also likely wonder how the start of your visas/travel dates correlate with one another.
Since you're traveling with a family member who is under a different visa, my advice is to just ask the person at the kiosk. Make it clear that you're traveling together but are either parting ways or staying together after immigration control.